The great guns were filled with powder to the muzzle, and then buried two-thirds of their length in the earth.
The whole mass of siege equipage was piled above them, and a train of gunpowder was laid to the store in the centre.

The men then drew off to a distance.

A match was applied to the train, and the whole blew up with a tremendous explosion.
The shock was heard in the faraway camp of William, and he knew that his cavalry had arrived too late to avert the catastrophe he feared.

They had, indeed, just arrived within sight of the spot when the explosion took place.

They rode on at full speed, only to find the vast pile of ruined woodwork blazing furiously.